🚀 go-pugleaf

In article <122...@linus.mitre.org>, jcmo...@mwunix.mitre.org (Joe Morris) writes:
     Also, 9-track tape is *always*
     written in odd parity, so you don't have to specify that option.

This isn't strictly true of all drives.  My first Unix machine, a
Perkin-Elmer running Wollongong v6 (as opposed to Bell Labs v6, whose C
compiler grew the stack in the other direction), had a tape drive (actually
I think the controller specifies this) that always wrote even parity, and
ignored (!) parity on reads.  Our Vax 11/780 with TU-58 drives refused to
read tapes with even parity.  So I translated them on a pdp-11 that always
wrote odd parity but would sense parity on reads, and switch to whatever
parity was used to write the tape.

Remember DECtape?  18 tracks, 3/4 inch wide.  Half the tracks were redundant
copies of the other half.